Record code slots that may point to evacuation candidate objects after deoptimizing them.

src/heap/mark-compact.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include "src/base/bits.h"
 #include "src/heap/spaces.h"
 
@@ skipping 400 matching lines @@
   static bool AddTo(SlotsBufferAllocator* allocator,
                     SlotsBuffer** buffer_address, SlotType type, Address addr,
                     AdditionMode mode);
 
   // Eliminates all stale entries from the slots buffer, i.e., slots that
   // are not part of live objects anymore. This method must be called after
   // marking, when the whole transitive closure is known and must be called
   // before sweeping when mark bits are still intact.
   static void RemoveInvalidSlots(Heap* heap, SlotsBuffer* buffer);
 
   // Eliminate all slots that point to the given invalid_object.

[Michael Starzinger, 2015/07/03 11:24:55]

nit: Comment no longer applies.

[Hannes Payer (out of office), 2015/07/03 11:26:53]

Done.

   static void RemoveObjectSlots(Heap* heap, SlotsBuffer* buffer,
-                                HeapObject* invalid_object);
+                                Address start_slot, Address end_slot);
 
   // Ensures that there are no invalid slots in the chain of slots buffers.
   static void VerifySlots(Heap* heap, SlotsBuffer* buffer);
 
   static const int kNumberOfElements = 1021;
 
  private:
   static const int kChainLengthThreshold = 15;
 
   intptr_t idx_;
@@ skipping 301 matching lines @@
 
   // The following four methods can just be called after marking, when the
   // whole transitive closure is known. They must be called before sweeping
   // when mark bits are still intact.
   bool IsSlotInBlackObject(Page* p, Address slot, HeapObject** out_object);
   bool IsSlotInBlackObjectSlow(Page* p, Address slot);
   bool IsSlotInLiveObject(Address slot);
   void VerifyIsSlotInLiveObject(Address slot, HeapObject* object);
 
   // Removes all the slots in the slot buffers that are within the given
-  // invalid_object.
-  void RemoveObjectSlots(HeapObject* invalid_object);
+  // address range.
+  void RemoveObjectSlots(Address start_slot, Address end_slot);
 
  private:
   class SweeperTask;
 
   explicit MarkCompactCollector(Heap* heap);
   ~MarkCompactCollector();
 
   bool WillBeDeoptimized(Code* code);
   void EvictPopularEvacuationCandidate(Page* page);
   void ClearInvalidSlotsBufferEntries(PagedSpace* space);
@@ skipping 272 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_MARK_COMPACT_H_